Composition of the mother’s milk III., Macro and micro element contents (Review)

Abstract

The authors have analysed macro and micro element contents of the mother’s colostrum and mother’s milk in comparison with the newest publications. Calcium contents of the mother’s milk varied in most of the studies between 84 and 462, while phosphorus contents varied from 17 and 278 mg/l. The amount of both calcium and phosphorus increased during lactation, but none of these elements was affected by calcium and phosphorus level of the serum, the vitamin supply, age and smoking. Average magnesium concentration of the mother’s milk is 30 mg/l, which is not affected by age, vitamin D supply, lactation and diabetes, and even the magnesium supply increases the first day only the magnesium contents of the milk. Sodium contents of the colostrum decreases from 300−400 mg/l to 120−250 mg/l, potassium contents from 600−700 mg/l to 400-550 mg/l, chloride contents from 600−800 mg/l to 400−500 mg/l in the mature milk. Some of the micro elements occur bonded in protein in the milk, which increase the efficiency of the absorption. Iron contents of mother’s milk were found in extreme cases between 0.04−1.92 mg/l, on average 0.40 mg/l, which is not affected by the environment, the mother’s nutriment, the iron intake and the contraceptive preparations. Its absorption from the mother’s milk is extraordinarily favourable, therefore even a low iron contents are sufficient to satisfy the needs of the babies. Copper contents of the mother’s milk vary between 0.03−219 mg/l, on average 0.350 mg/l. The effect of lactation on the copper contents is controversial, and it appears that the copper contents are not influenced by either the nutriment or the copper intake. Its major part if bonded to protein, therefore its absorption is very favourable. Zinc contents of the mother’s milk were measured to be between 0.15−5.41 mg/l, it is difficult to specify an average value due to variations of order of magnitude. Similarly, there are extreme value obtained for the manganese contents 0.8−21.5 μg/l, which can be explained by the different manganese intake of the mothers, or by extreme manganese burden of the environment. Out of the other micro elements, the authors analyze the chromium, nickel, cobalt, molybdenum, selenium, iodine and silicon contents of the mother’s milk, while among toxic trace elements cadmium, lead and mercury contents. Amount of latter ones in the mother’s milk is affected by smoking, the polluted urban air, exhaust gas of the motor vehicles, the polluted environment and by the number of amalgam fillings. Cadmium contents of the mother’s milk were measured to be between 0.07−3.8 μg/l, but in an extremely polluted urban environment it reached even the value of 24.6 μg/l. Even more extreme values were measured for the lead, as its concentration ranged from a couple of tenth to 350 μg/l. Lead contents were increased mainly be the polluted urban air, however, its amount decreased after the unleaded fuels have been widely used. Mercury contents of the mother’s milk were affected mainly be number of amalgam fillings and the surface of the fillings. Its amount varied from 0.10 to 6.86 μg/l.